Re: [PATCH v3 06/10] pwm: Add NVIDIA Tegra SoC support

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* Stephen Warren wrote:
> Thierry Reding wrote at Wednesday, February 22, 2012 8:17 AM:
> > This commit adds a generic PWM framework driver for the PWFM controller
> > found on NVIDIA Tegra SoCs. The driver is based on code from the
> > Chromium kernel tree and was originally written by Gary King (NVIDIA)
> > and later modified by Simon Que (Chromium).
> 
> > diff --git a/drivers/pwm/pwm-tegra.c b/drivers/pwm/pwm-tegra.c
> 
> > +static int tegra_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
> 
> > +	/*
> > +	 * Convert from duty_ns / period_ns to a fixed number of duty
> > +	 * ticks per (1 << PWM_DUTY_WIDTH) cycles.
> > +	 */
> > +	c = duty_ns * ((1 << PWM_DUTY_WIDTH) - 1);
> 
> The driver in ChromeOS has the following extra line here:
> 
>     c += (period_ns / 2);
> 
> and the following extra line in the comment above:
> 
>     Also, make sure to round to the nearest integer during division.
> 
> I don't know the HW well enough to know if that line should be present?
> 
> Otherwise, this looks similar enough to the ChromeOS driver, so:
> 
> Acked-by: Stephen Warren <swarren@xxxxxxxxxx>

Those probably weren't there yet when I prepared the first series. I'll have
another look will sync up with it after testing that it still works.

Thierry

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